Traditional hospital pillow speakers and handheld pendants do not typically receive power independent from the nurse call system to which they are connected. A typical arrangement is illustrated in FIG. 1. The limited power supply capabilities of the nurse call system may restrict the capabilities and features of such devices. In other cases, pillow speakers and pendants may be passive devices which do not consume power at all, and may merely provide passive contact closure switches for signaling to the nurse call master station. Pillow speakers that draw power from the nurse call system are subject to the same power interruptions experienced by the nurse call system.
Interruptions in the electrical power supplied to hospitals, whether to the primary power system or any number of subsystems, may occur frequently due to the requirements for hospitals to test emergency power supply systems. Such interruptions are termed “brownouts.” Brownouts may occur for very short periods as the emergency system switches from a normal power source to an alternate power source, or for longer periods of time depending on the condition and performance of the emergency system or the type of test. Further, certain electrical branches may be deemed non-essential and will not switch over to an alternative power source in the absence of a primary source. Brownouts may also occur outside of planned hospital tests due to weather or other natural events disrupting the electrical grid supplying the hospital, or due to unplanned mechanical or electrical equipment failures.
As pillow speakers grow in capability and offer more features, such as tablets or other patient interaction devices (PIDs), the power demands of the pillow speakers also increase. Electrical power may be supplied to a pillow speaker from a secondary source separate from the power supplied from the nurse call patient station, such as a branched circuit connected to a wall outlet. As such PIDs are dependent on secondary power, they may not have the benefit of the nurse call system for protection from power interruption. As such, there is a critical, long-felt need for a nurse call pillow speaker with improved resistance to brownouts.